VHF无线电话VoIP网关关键技术的研究

发布时间：2018-02-12 03:24

本文关键词： VHF通信 VTS VoIP技术话音编解码　出处：《大连海事大学》2017年硕士论文　论文类型：学位论文

【摘要】：船舶交通管理信息系统(VTS)作为海上交通指挥控制的中心,旨在提高海上交通运输效率,减少水上交通事故等。VHF通信子系统作为其重要组成,在VTS中心和船舶之间建立了有效的信息联系。传统VTS中的VHF通信子系统采用专用岸基VHF通信设备,其缺点是工程造价高,可扩展性相对较差。目前,VoIP技术正逐步运用在VTS的VHF通信系统中,其采用商业的话音网关处理技术,未针对VHF通信特点做出调整和改进。因此,VHF通信系统存在话音与控制信号传输不同步的问题,同时话音传输不完整且质量较差。本文主要研究一套基于船用VHF设备和VoIP技术的VHF通信子系统。首先,针对船用VHF设备,提出了基于VoIP技术的VHF通信子系统的整体设计方案,对VHF-VoIP网关各部分关键模块进行了设计和分析。其次,针对VHF通信子系统中话音和控制信号不同步的缺点,提出了两种VTS中VHF通信系统专用的网络封包模型。将控制和话音信号通过网络协议封装打包,有效解决了话音传输不完整和质量差等问题。然后对LPC、DPCM、ADPCM和CS-ACELP压缩编解码算法进行对比分析,采用了 CS-ACELP编解码算法,并提出改进的结构简单的多特征值VAD预编码算法。在高压缩比的情况下,降低了算法的复杂度,提高了 VHF通信的实时性和灵活性。最后,通过本文设计的神经网络话音评价系统验证了该编解码算法的有效性。本课题研究结果表明,VHF-VoIP网关不仅实现了 VHF终端与VHF收发信机之间的实时通话,而且实现了 VTS中VHF终端对基站VHF收发信机的远程控制和状态回执,同时优化了 VHF系统信息的数字化传输和话音通信的数字化控制管理,有效解决了 VTS系统中利用VoIP所实现的VHF通信子系统所存在的问题,利用本课题提出的VHF-VoIP网关,可实现船用VHF设备在VTS系统中的应用。
[Abstract]:As the center of maritime traffic command and control, VTS (ship Traffic Management Information system) is an important part of VHF communication subsystem, which aims to improve the efficiency of maritime traffic and reduce maritime traffic accidents. An effective information connection is established between the VTS center and the ship. The traditional VHF communication subsystem in VTS uses special shore-based VHF communication equipment, which has the disadvantage of high engineering cost. At present, the VoIP technology is gradually used in the VHF communication system of VTS, which adopts the commercial voice gateway processing technology. The communication characteristics of VHF have not been adjusted and improved. Therefore, the voice and control signal transmission is out of sync in VHF communication system. At the same time, the voice transmission is incomplete and the quality is poor. This paper mainly studies a set of VHF communication subsystem based on marine VHF equipment and VoIP technology. Firstly, the whole design scheme of VHF communication subsystem based on VoIP technology is proposed for marine VHF equipment. The key modules of VHF-VoIP gateway are designed and analyzed. Secondly, the disadvantages of voice and control signal synchronization in VHF communication subsystem are analyzed. In this paper, two kinds of network packet models for VHF communication system in VTS are proposed. The control and voice signals are packaged by network protocol. The problems such as incomplete voice transmission and poor quality are effectively solved. Then the CS-ACELP coding and decoding algorithms are compared and analyzed with CS-ACELP compression coding and decoding algorithms. An improved multi-eigenvalue VAD precoding algorithm with simple structure is proposed. In the case of high compression ratio, the complexity of the algorithm is reduced, and the real-time and flexibility of VHF communication is improved. The effectiveness of the algorithm is verified by the neural network voice evaluation system designed in this paper. The research results show that the VHF-VoIP gateway not only realizes the real-time communication between the VHF terminal and the VHF transceiver. Furthermore, the remote control and status receipt of the base station VHF transceiver by VHF terminal in VTS are realized. At the same time, the digital transmission of VHF system information and the digital control management of voice communication are optimized. The problem of VHF communication subsystem realized by VoIP in VTS system is solved effectively, and the application of marine VHF equipment in VTS system can be realized by using the VHF-VoIP gateway proposed in this paper.
【学位授予单位】：大连海事大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TN916.5;TN914

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